Fatigue Resistance of Two Different Materials Used as Retentive Attachments in Implant Supported Overdenture after Immersion in Denture Cleansing Solution: An In Vitro Comparative Study

Abstract

This in vitro study compared the fatigue resistance of two polymeric materials (Nylon and Polytetrafluoroethylene (PTFE)) used as retentive attachments in implant-retained overdentures after immersion in denture cleansing solution. A total of 24 samples (N=24), of which 12 capsule-shaped samples of commercially available nylon material from ADIN dental implants, India, and similar sized and shaped 12 PTFE (medical grade) capsules custom fabricated from AAA Industries, Mumbai was obtained. Six samples of each material were immersed in distilled water and six samples in Clinsodent denture cleanser, simulating an 8–h daily immersion of the denture for a period of 2 years. After completion of the immersion protocol, samples were subjected to 2900 fatigue cycles using the Universal Testing Machine (UTM), simulating 4 cycles per day of removal and insertion of the overdenture for a duration of 2 years. Before and after immersion, the wear of the samples was assessed for internal and external diameter changes using the Sipcon Inspection System. The statistical analysis of the obtained results was tested by applying the paired-t test, Fisher analysis of variance, and Tukey’s honest significant difference test, with a probability value less than 0.05 used as statistically significant. Statistically significant differences were observed after immersion in denture cleanser for nylon and PTFE. The greatest fatigue for ID, IHL, and IVL was demonstrated in nylon immersed in Clinsodent at p = .000. ED and EHL of PTFE in distilled water showed greater deformation than others ( p = .000). PTFE attachments have shown better fatigue resistance after immersion in Clinsodent denture cleanser. Nylon material immersed in distilled water as well as in Clinsodent cleanser showed greater deformation after fatigue cycles.